Kilogray is 1000 gray units.
Kilograys to Rads Converter — kGy to rad
Convert Kilogray (kGy) to Rad (rad) using the exact conversion factor (1 kilogray = 100,000 rad). See the formula, worked examples, conversion table, and common uses.
Kilograys to Rads converter
Converter
Radiation Converter
Convert radioactivity, absorbed dose, and equivalent dose units by compatible radiation family.
Context values
Some unit families need one extra value for a physically accurate result.
Rad is 0.01 gray.
Result = input x 1000 / 0.01.
Absorbed Dose units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Kilograys to Rads
Kilogray and Rad both belong to the radiation-measurement family, though radiation quantities fall into genuinely distinct categories: absorbed dose (gray, rad) measures energy deposited in matter, equivalent dose (sievert, rem) weights that for biological harm, and activity (becquerel, curie) measures how often a radioactive source decays — this page only converts between units of the same kind. Specifically: Kilogray is 1000 gray units, and rad is 0.01 gray.
Formula
rads = kilograys × 100000
This factor comes from each unit's defined relationship to the category's base unit: 1 kilogray equals 1000 base units, and 1 rad equals 0.01 base units, so dividing one by the other gives the direct kilogray-to-rad factor of 100000.
Simple example
1 kGy × 100000 = 100,000 rad
1 kilogray = 100,000 rads.
Real-world example
10 kGy × 100000 = 1,000,000 rad
10 kilograys = 1,000,000 rads.
Conversion table
| Kilogray (kGy) | Rad (rad) |
|---|---|
| 0.001 kGy | 100 rad |
| 0.01 kGy | 1,000 rad |
| 0.1 kGy | 10,000 rad |
| 1 kGy | 100,000 rad |
| 10 kGy | 1,000,000 rad |
| 100 kGy | 10,000,000 rad |
Reverse conversion: Rad to Kilogray
1 rad × 0.00001 = 0.00001 kGy
1 rad = 0.00001 kilograys.
kilograys = rads × 0.00001
For a page dedicated to this direction, see Rad to Kilogray.
Understanding the Kilogray (kGy)
Kilogray is 1000 gray units.
Understanding the Rad
Rad (rad) measures absorbed radiation dose. 'Radiation absorbed dose' — the US customary unit of absorbed radiation dose, fixed at exactly 0.01 gray. It is classified as a non-SI unit, still common in the US.
Where it's used: Still used in some US medical and historical contexts alongside the SI gray
Rad vs. gray. Both measure absorbed radiation dose; the gray is the modern SI unit while the rad is the older US customary unit, related by 1 gray = 100 rad exactly.
Uses of the Rad today
- US radiation therapy dose records (historically)
- US nuclear regulatory and medical physics contexts
Rad — sources
- NIST Guide to the SI, Appendix B — Lists the rad among non-SI units with an exact SI equivalence.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many rads are in 1 kilogray?
1 kilogray equals 100,000 rads, using the exact defined conversion factor rather than an estimate.
How do I convert kilogray to rad?
Multiply the kilogray value by 100000. The converter above does this instantly to whatever precision you set.
How do I convert rad back to kilogray?
Use the reverse factor: 1 rad equals 0.00001 kilograys. You can also use the swap control in the converter above to flip the direction instantly.
What is a kilogray?
Kilogray (kGy) is a unit of radiation.
What is a rad?
Rad (rad) measures absorbed radiation dose. 'Radiation absorbed dose' — the US customary unit of absorbed radiation dose, fixed at exactly 0.01 gray. It is classified as a non-SI unit, still common in the US.
Is the kilogray to rad conversion exact?
Yes. 'Radiation absorbed dose' — the US customary unit of absorbed radiation dose, fixed at exactly 0.01 gray. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
What is the difference between rad vs. gray?
Both measure absorbed radiation dose; the gray is the modern SI unit while the rad is the older US customary unit, related by 1 gray = 100 rad exactly.